package com.club.subject.domain.util;


import com.alibaba.fastjson.JSON;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import org.apache.commons.lang3.StringUtils;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.TimeUnit;
import java.util.function.Function;

@Component
public class CacheUtil<V> {
    private Cache<String, String> localCache =
            CacheBuilder.newBuilder()
                    .maximumSize(5000)
                    .expireAfterWrite(10, TimeUnit.SECONDS)
                    .build();

    public List<V> getResult(String cacheKey, Class<V> clazz,
                             Function<String, List<V>> function) {
        List<V> resList = new LinkedList<>();
        String content = localCache.getIfPresent(cacheKey);
        if (!StringUtils.isBlank(content)) {
            resList = JSON.parseArray(content, clazz);
        } else {
            resList = function.apply(cacheKey);
            if (!CollectionUtils.isEmpty(resList)) {
                localCache.put(cacheKey, JSON.toJSONString(resList));
            }
        }

        return resList;
    }
}
